Collagen scaffolds have been used in tissue repair and tissue reconstruction. The scaffolds are usually crosslinked to provide the degree of wet strength and measured resistance to dissolution needed for these applications. In general, the crosslinking of collagen sponges or foams reduces or degrades the normal binding sites to which cells and certain molecules secreted by cells attach. Furthermore, collagen sponges, gelatin sponges or collagen gels, while biologically active, lack biological activity typically present in the extracellular matrix environment due to the lack of non-collagen components and thus information which binds to collagen or to non-collagen components themselves. Because of their deficiencies, collagen scaffolds crosslinked by known methods induce little regeneration in vivo or serve poorly as histiotypic and organotypic models in vitro.
A need exists, therefore, for an improved biopolymer form that overcomes or minimizes the above-mentioned problems and preserves the natural structure of the collagen.